Shoe having heel core molded therein



Jan. 16, 1968 R. LVBOURASSA ETAL 3,36

SHOE HAVING HEEL CORE MOLDED THEREIN Filed March 1, 1965 2 Sheets-Sheet1 INVENTORJ Jan. 16, 1968 R. L.. BOURASSA ETAL 3,353,343

SHOE HAVING HEEL CORE MOLDED THEREIN Filed March 1, 1965 2 Sheets-Sheet2 United States Patent M SHGE HAVING HEEI: CORE MOLDED THEREIN Robert L.Bourassa, Wenham, and Julius G. Winkler,

Lexington, Mass., assignors to International Vulcanizing Corporation,Waltham, Mass., a corporation of Massachusetts Filed Mar. 1, 1965, Ser.No. 436,242 1 Claim. (Cl. 36-32) ABSTRACT OF THE DISCLOSURE A shoehaving a continuous bottom comprised of a bottom-forming compositionmolded to the lasting margin and including at the heel end a heel coreof wood or the like.

The principal objects of the invention are to provide a shoe of theforegoing kind with a heel comprised of a core and a cover soconstructed that the cover will not separate from the heel; to provide aheel cover so constructed that it cannot separate from the heel coreeven though the core is incompatible with the cover and does not adherethereto; to provide a heel in which the core constitutes the majorportion of the volume of the heel and is comprised of a material lighterthan the cover so as to lessen the weight of the heel; and to provide aheel in which the core is rigid, inexpensive and comprised of readilyavailable material.

As herein illustrated, the shoe has a heel comprising a core and a coverwherein there is means extending transversely of the heel core from oneside to the other, connected at its ends to the wall of the cover atopposite sides of the core which prevent the core from Working out ofthe pocket formed by the cover and/ or separation of the wall of thecover from the core. The aforesaid means in the preferred form of theinvention comprise a plurality of longitudinally spaced, parallel tiesextending transversely of the heel core with their ends integral withthe wall of the cover at opposite sides of the core. The ties may besituated in grooves in the top of the heel core or holes through theheel core. Optionally, the heel may comprise a core spaced from thebottom of the upper and a cover comprising a side Wall peripherallythereof, a bottom wall constituting a heel lift, and a top wallextending across the top of the core between it and the bottom of theupper which is integral at its edge with the upper edge of the side walland hence prevents separation of the core from the pocket formed by thecover and/or separation of the side wall of the cover from the core.

In accordance with the preferred method, a core in the form of a heelwedge is provided containing a plurality of transversely extendingpassages, either in the surface which is to have contact with the bottomof the lasted upper or through the wedge from one side to the other; thewedge is held engaged with the bottom of the lasted upper and thebottom-forming composition is applied by injection molding to form anoutsole at the forepart, a cover about the heel wedge and to fill thepassages. Alternatively, the top of the wedge is held spaced from thebottom of the upper and the bottom-forming composition is injected toform a cover about the heel wedge and to fill the space between the topof the heel wedge and the bottom of the lasted upper. Positioning pins,spacing pins and supporting pins are provided for properly locating andholding the heel wedge in position at the bottom side of the lastedupper during injection.

A novel heel Wedge is employed in making shoes embodyirig the aboveadvantages, characterized in that it contains longitudinally spaced,parallel, transversely ex- 3,363,343 Patented Jan. 16, 1968 tendingpassages in its upper surface which provide, when the top of the heelWedge is held against the bottom of the lasted upper, groovestransversely of the wedge through which the bottom-forming compositionis adapted to flow during the formation of the bottom.

The invention will now be described in greater detail with reference tothe accompanying drawings wherein:

FIG. 1 is a side elevation of a shoe having a bottom and heel formed byinjection molding;

FIG. 2 is a plan view looking into the top opening of the shoe shown inFIG. 1;

FIG. 3 is a transverse section taken on the line 3-3 of FIG. 2;

FIG. 4 is a transverse section taken on the line 4-4 of FIG. 2;

FIG. 5 is an elevation of the wedge;

FIG. 6 is a plan view of the top of the wedge;

FIG. 7 is a bottom view of the wedge;

FIG. 8 is a fragmentary elevation of an alternate form of the inventionwherein holes are formed through the wedge from one side to the other;

FIG. 9 is a fragmentary bottom view of a last showing an upperstring-lasted thereto about a plurality of gauge pins at the heel endand with a wedge positioned within the gauge pins, the latter beingshown-in dot and dash lines;

FIG. 10 is a fragmentary elevation at the heel end of the shoe showingspacing and attaching means for locating the heel Wedge and holding itin place during injection; and

FIG. 11 is a transverse section showing the core located, spaced andattached to the bottom side of the last preparatory to injection.

Referring to the drawings, the shoe comprises a conventional upper 10made of leather, fabric or man-made material and a bottom formed of aplastic composition, such as polyvinyl chloride, consisting of aforepart 12 and heel 14 applied to the upper by injection molding. Theheel 14, as illustrated, is of the wedge-type and contains a heel core16 shown dotted in FIG. 1.

As herein illustrated, the core 16 is a wedge, as shown in FIGS. 5, 6and 7, comprised of a natural material or a composition which isinexpensive, readily available, rigid, light in weight, durable and notadversely aiiected by the moisture of the foot. It is the purpose ofthis invention to enable use of any such material for a core whether ornot it is compatible with or will become permanently adhered to thesubstance of the bottom-forming composition without special treatment ofits surface and without the core Working out of the cover or the coverseparating from the core.

In the preferred form of the invention this is accomplished by providingthe wedge with a plurality of transversely spaced, parallel grooves 18in its upper surface 20, as shown in FIGS. 5 and 6, holding the wedgeagainst the bottom of the lasted upper within a mold cavity (comprisedof a mold ring against the top of which the lasted upper is held and asole plate supported at the lower side of the ring for movement relativeto the ring to control the depth of the mold cavity) and injecting thebottom-forming composition to fill the cavity so as to .form an outsoleat the forepart and a heel cover about the wedge. The cover comprises aperipheral side wall 22 and a heel lift 24, within which the core, thatis, the .wedge is contained as shown in FIGS. 3 and 4. During injectionthe bottom-forming composition flows through the grooves 18 between theupper surface 20 of the wedge and the bottom of the lasted upper,forming ties 26, one of which is shown in FIG. 3, which are integral attheir opposite ends with the opposite sides of the peripheral side wall22 and thus prevent the heel Wedge from Working out of the pocket formedby the cover or separation 3 of the cover from the sides of the heelwedge. As herein illustrated, there are five grooves 18 which extendacross the upper surface 20 of the wedge from one side of the other. Thegrooves are semicircular in cross-section and have a diameter ofapproximately of an inch. The bottom-forming composition which flowsinto these grooves fills them and forms with the portions of the surface20 between them a smooth surface corresponding in contour to the wedgesurface prior to grooving.

FIG. 4 shows the junction of the bottom-forming composition with thelasting margin which is string-lasted and embodies no insole so that theupper surface of the wedge and ties are exposed inside the shoe as shownin FIG. 2.

Alternatively, instead of employing grooves 18 in the upper surface ofthe wedge, a plurality of transverse holes 27, such as shown in FIG. 8,may be used. The holes are formed through the wedge from one side of theother so that continuous ties will be formed by flow of thebottomforming composition through the holes from one side to the other.

In order to hold the heel core or wedge in place, in proper relation tothe bottom side of the lasted upper during injection, use is made ofgauge pins 30 fixed to the bottom of the last as shown in FIG. 9. Thesepins are employed to control the position of the inner edge of thelasting margin when the latter is pulled onto the last by thedraw-string and provide convenient means for locating the heel core bothtransversely and longitudinally of the bottom. Additional pins 32 may befixed to the bottom of the last at the median line upon which the 2 thebottom during injection. The wedge may contain in its upper surfacedrilled holes 34 for receiving the pins 32 or the pins 32 may beprovided with pointed ends and the wedge pressed onto these ends.

If desired, the heel core, as shown in FIGS. and 11, may be held spacedfrom the bottom of the lasted upper by spacing pins 36 fixed in thebottom of the last at opposite sides of the median line, so that whenthe heel core is impaled on the holding pins 32 within the locating pins30 there is a continuous space between the upper surface of the core andthe bottom of the lasted upper which will be completely filled withbottom-forming composition thus forming a top wall coextensive with theheel core and integral with the upper edge of the side wall. In thisalternative form of the invention, the heel core is completely enclosedwithin the cover and hence there is no possibility of separation of thecover from the core.

4 However, this construction does not provide quite the rigidityafforded by the structure shown in- FIGS. 3 and 4, is not as economicalof material, is not as light in weight and does not afford the footcomfort of a core exposed at the inside of the shoe.

The pins 32 and 36 are all of very small diameter so that when the shoeis stripped from the last the holes left are barely discernable andhence arenot objectionable.

The heel core wedge as described herein is "made of wood, however, anyother suitable material embodying the desired characteristics ofrigidity, light-weight, low cost and resistance to foot moisture may besubstituted for the wood heel since the material does not have to be compatible with or adherent to the bottom-forming composition which formsthe cover.

It should be understood that the present disclosure is for the purposeof illustration only and that this invention includes all modificationsand equivalents which fall within the scope of the appended claim.

We claim:

1. In a shoe comprising an upper having a turned in lasting margin and aheel core at the heel end; a bottom comprising a continuous layer ofbottom-forming composition covering the forepart and heel core, and anintegral membrane extending transversely of the heel core between thebreast and the back line joining the side wall 7 portions of the heelcore covering to each other, said heel core including a plurality oftransverse grooves extending entirely across the top of the coreconfronting the bottom of the shoe at the heel end thereof and aplurality of membranes extending through said grooves, the top of theheel core, the inner surface of the lasting margin and the upper surfaceof the membranes situated in the grooves at the top of the heel beingflush.

References Cited UNITED STATES PATENTS 1,706,504 3/1929 Warren 12145 X1,977,576 10/1934 Dunker.

2,016,178 10/1935 Riddock 36-44 X 2,151,314 3/1939 Burger 36-342,412,042 12/1946 Gotts'chalk 12142 2,918,703 12/1959 Beal 264-2753,109,701 11/1963 Jacquet 264244 3,116,566 1/1964 Ferreira 3630 JORDANFRANKLIN, Priniary Examiner. H. HAMPTON HUNTER, Assistant Examiner.

